MONTPELIER — One of the fiscal wellsprings used to fund infrastructure repair in Vermont could soon begin to dry up as elected officials consider reduced borrowing to preserve the state’s golden credit rating.

The state will borrow nearly $160 million over the next two years to pay for everything from the rehabilitation of government buildings to the construction of new police barracks and a health laboratory.

But Vermont’s bonding capacity, as well as the list of items funded by it, could soon shrink as debt experts weigh the benefits of borrowing against its impact on the state’s AAA bond rating.

A new analysis from the Capital Debt Affordability Advisory Committee indicates that borrowing levels may have to come down as much as 37 percent in the next two-year capital bill in order to retain triple-A status. And that could mean shaving as much as $26 million annually from a fiscal mechanism on which lawmakers have relied to address the long backlog of infrastructure needs.

“The Shumlin administration has had a real eye on trying to invest in infrastructure,” Administration Secretary Jeb Spaulding said Friday. “But our goal would be to do that without jeopardizing the state’s bond rating.”

The CDAAC is a seven-person panel that conducts annual reviews of the “size and affordability” of taxpayer-funded general-obligation debt, and makes recommendations to the governor and Legislature as to what level of bonding they should authorize in the years ahead.

The recent analysis wouldn’t affect the current capital bill, which allocates funding for projects in fiscal years 2014 and 2015. But the analysis, which State Treasurer Beth Pearce emphasized is still very preliminary, suggests Vermont may need to ratchet down borrowing in fiscal years 2016 and 2017 if it wants to retain its immaculate bond rating.

“Our metrics do indicate some tightening potentially,” Pearce said.

Lawmakers will pass the next two-year capital bill in calendar year 2015. Another possible scenario modeled by the CDAAC would require a nearly 16-percent reduction in borrowing in order to keep the triple-A rating safe. The panel won’t make its final recommendation on borrowing limits until September of 2014.

“But we think it’s prudent to provide this information to the Legislature now, so this gives them 18 months lead time to facilitate long-range planning,” Pearce said.

Ratings agencies like Moody’s rely on three primary factors in determining a state’s credit worthiness: debt per capita, debt as a percentage of personal income, and debt service as a percentage of revenue.

Pearce and Spaulding, both of whom sit on the CDAAC, said that as others states have dialed back on borrowing, Vermont’s numbers could begin to fall outside the ratings agencies’ desired ranges.

“The ratings business is largely a relative one — where do we stand relative to other states and other investments?” Spaulding said. “And what’s happening is other states, because of the economic situations they’re facing, have been ratcheting down the amount of borrowing they’re doing, kind of like consumers do when they’re in a bad situation financially.”

The state already faces a long backlog of projects fighting to make it into the capital bill. And a significant portion of the fiscal year 2016 capital bill is already spoken for, due to the $9.8 million Vermont will need to allocate for the completion of the new state office complex in Waterbury.

Spaulding and Pearce, however, said the state needs to exercise fiscal discipline when it comes to bonding, even in the face of legitimate capital needs.

Vermont’s high credit marks allow it to borrow at rates lower than it would otherwise. Those lower interest payments translate into significant savings, when applied to Vermont’s considerable debt load. Vermont pays $74 million annually to cover debt service on nearly $550 million in outstanding general-obligation loans.

The state also provides moral obligation to the loans taken out by state authorities like the Vermont Municipal Bond Bank, Vermont Housing Finance Agency and Vermont Student Assistance Corporation, improving the interest rates those entities are able to secure.

“So from our end we need to take a very, very prudent approach to manage our debt so we can manage not just our own capital needs, but also the larger picture of affordable housing and municipal bonding and college loans,” Pearce said.

“We have no interest in going to double-A. We think it would cost the state millions over the years,” Spaulding said. “So I think it’s a question of priority-setting. And we’re willing to do that.”

It’s been six years since Vermont regained the triple-A bonding rating that it lost in 1971. Spaulding, a former four-term state treasurer, said the Legislature has never exceeded the bonding limits recommended by the CDAAC.

“The single biggest feather we have on our caps (from the ratings agencies’ perspective) is a disciplined approach to debt management,” Spaulding said. “And we wouldn’t want in any way to tarnish our best asset.”